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Discussion Starter · #1 ·
Hello All
I used to have an 03 SVTf euro (screaming yellow) that I was in love with. I really regret selling it and I'm thinking about going back to one as a daily. Since then I've had a few Honda projects, a Mazdaspeed 3, and now I've got a Miata I plan to make my project. I had a quick question on some info that I can't seem to find. I'm really sorry if it's already listed on here and I just didn't see it. I searched around a bit and couldn't find it in the FAQs.
Does anyone know what kind of normal compression numbers I should see on all 4cylinders for the 2.0 svt zetec on a standard compression test?
Or perhaps a nice link to a .pdf for a factory service manual that might have them or even the factory procedure for the test?
Anyway here's a few pics of my old car:



After reading the production numbers on here I'm really shooting myself for letting it go....
Chris
 

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The numbers can vary due to cam timing, engine temp, cranking speed, etc.

As long as the pressures are in the same general area it's good.
 

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Discussion Starter · #4 ·
Thanks for the responses.
I'm aware of the differences you can see given different gauges, different temperatures, and other factors. Im also aware of what a full leakdown test can tell you vs just a basic compression test. I have to say I've never seen anyone relate the number of degrees of timing advance they have tuned the car for (i assume for performance) to the compression psi in the combustion chamber. I don't think those things are related at all. Besides that if you run your car harder with more advanced timing you may loose compression faster.

Every engine I've ever seen has a minimum standard (usually hot) and a max difference between cylinders thats acceptable. Im just looking for those exact specs if anyone has them.
In example here's the specs for my old speed 3



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There are no exact specs for this car in regards to compression as mentioned in my first post. There are a number of variables that will affect the actual number. Just make sure the numbers are close to each other (within 10%).
 

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Usually as long as there not stupid low like 40psi and within 10% you are usually good. Also cam timing can affect the amount of pressure in your cylinder, due to valve over lap, and valve closing sooner or later.
 

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Discussion Starter · #7 ·
thanks again for all the info
i've got this on my list of something to check on the cars i've been looking at - i usually won't buy a car like this with higher mileage unless the seller will make the test part of the deal...
 
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